Increased Young's modulus and hardness of Col1a2oim dentin

Mice harboring the Col1a2(oim) mutation (oim) express dentinogenesis imperfecta. To determine the effect of Col1a2 genotype on tissue mechanical properties, we compared Young's modulus and hardness of dentin in the 3 Col1a2 genotypes. Upper incisors were tested by nanoindentation. Genotype had a significant effect on Young's modulus, but there was not a simple mutant allele dosage relationship. The effect of genotype on hardness did not reach significance. Hardness and Young's modulus were greater near the dento-enamel junction than near the pulp chamber. Greater hardness and Young's modulus values near the dento-enamel junction reflected continued mineralization of the dentin following its initial synthesis. Analysis showed the mechanical data to be consistent with Fourier transform infrared and backscattered electron microscopy studies that revealed increased mineralization in oim bone. Analysis of the data suggests that clinical fragility of teeth in oim mice is not due to deficiencies of hardness or Young's modulus, but may be due to defects in post-yield behavior or resistance to fatigue damage.

Gastrointestinal manifestations of chronic granulomatous disease

OBJECTIVE

Chronic granulomatous disease is a rare clinical entity characterized by recurrent infective and inflammatory complications. Patients are usually assigned to specialist centres, but nonspecialist clinicians may be required to treat these patients in the emergency setting. This review serves as a management guide to those clinicians who are faced with patients presenting with gastrointestinal manifestations of chronic granulomatous disease.

METHODS

This review is based on a literature search (Medline and NLM PubMed) with manual cross-referencing of all articles related to gastrointestinal chronic granulomatous disease.

RESULTS

Gastrointestinal tract involvement is present in most affected patients. Clinical presentation can mimic common surgical complications such as colitis, perianal sepsis, gastric outlet obstruction and liver abscess. A history of recurrent infections during childhood is common. Management involves haematological, microbiological, endoscopic and radiological investigations. Treatment modalities include early aggressive empirical antimicrobial therapy for sepsis, immunomodulation for inflammatory complications and surgical drainage of abscesses.

CONCLUSION

Early involvement of a centre with immunological expertise combined with aggressive management of complications significantly improves morbidity and mortality from this rare condition.

The recombinant HLA-B*5518 allele supports the evidence of conserved haplotype association of rare alleles

Allelic polymorphism of the major histocompatibility complex arises mostly from gene recombination. Intralocus gene recombination usually involves short fragments of DNA leading most commonly to single-nucleotide substitutions and rarely involves large fragments. Here, we report a new recombinant human leukocyte antigen (HLA)-B*5518 allele that has arisen via recombination of a large fragment of DNA spanning more than 70 nucleotides. During routine HLA typing of potential volunteer donors for the National Marrow Donor Program((R)), a new HLA-B allele was identified in two donors from Guam. The allele, B*5518, appears to be a product of recombination between B*5502 and B*40. Exons 1, 3, and 4 of the new allele belong to B*5502, whereas part of exon 2 belongs to one of B*40 alleles. Introns 1 and 2 appear to belong to B*55, suggesting that the recombination event may have occurred within the homologous parts of exon 2.

EXternal Pelvic REctal SuSpension (Express procedure) for rectal intussusception, with and without rectocele repair

Background

The results of conventional treatment for rectal intussusception and rectocele are unpredictable. The aim was to develop a less invasive surgical approach and to evaluate outcome in selected patients.

Methods

Seventeen patients (13 women; median age 47 (range 20–67) years) with rectal evacuatory dysfunction and rectal intussusception, 13 of whom had a rectocele, were selected. The intussusception was corrected by external pelvic suspension of the rectum, using collagen strips attached to the rectal wall and pubis. The rectocele was repaired with a collagen patch. Patients were assessed before and 6 months after surgery by symptom and quality of life questionnaires, anorectal physiological investigation and proctography, and were followed up for a median of 12 months.

Results

Sepsis requiring exploration occurred in two patients but there was no extrusion or need to remove the collagen. Of the 15 patients assessed after surgery, total symptom scores were significantly decreased (P < 0·001) and quality of life scores improved (P < 0·001). Proctographically, the degree of intussusception was improved in ten patients; six patients had normal postoperative proctograms. The rectocele was reduced in size in all patients, and was not demonstrable in eight.

Conclusion

An effective procedure for rectal intussusception and rectocele has been developed in a selected group of patients with marked evacuatory symptoms.

External pelvic rectal suspension (the Express procedure) for full-thickness rectal prolapse: evolution of a new technique

OBJECTIVE

The Délorme's operation for rectal prolapse is a safe procedure but has a high recurrence rate. We aimed to develop an operation akin to it, but designed to reduce this deficit.

PATIENTS AND METHODS

Thirty-one consecutive patients with rectal prolapse were included in the study. Initially, a conventional Délorme's procedure was performed and sutures or strips of Gore-Tex were attached circumferentially to the apex of the prolapse, tunneled subcutaneously, and anchored to the external surface of the pelvis. Subsequently, the procedure was modified. Acellular porcine collagen strips were used and buried within the apex without plication of the denuded rectal musculature. Patients were formally assessed preoperatively and four months postoperatively by symptom and quality of life questionnaires and subsequently by regular clinical review.

RESULTS

In the Gore-Tex group (N = 11; males:females = 10:1; mean age, 61 years) three patients underwent suture repair and eight had strip fixation. All suture repairs developed sepsis and one patient had a recurrence. Seven of the strip fixations (88 percent) developed sepsis that resulted in implant extrusion. There was one full-thickness and one mucosal recurrence after a median follow-up of 25 months. In the collagen group (N = 20; males:females = 2:18; mean age, 63 years), sepsis occurred in four patients, requiring surgical intervention in one patient (5 percent) (cf Gore-Tex group, P = 0.002). There was one mucosal and three full-thickness (15 percent) recurrences after a median follow-up of 14 months (cf Gore-Tex group, P = not significant). Significant improvements in symptom and quality of life scores were recorded in both groups at four months.

CONCLUSION

A new, minimally invasive perineal procedure for rectal prolapse has been developed and initial data testify to its relative safety provided collagen is used. It remains to be seen whether long-term recurrence rates will be lower than those of conventional perineal procedures.

Emerging new alleles suggest high diversity of HLA-C locus

Human leukocyte antigen (HLA)-C has only recently emerged as an important transplantation antigen and as a receptor for natural killer cells. Over the last few years, sequence-based typing (SBT) revealed the true diversity of HLA-C locus; however, the frequency at which new alleles are detected still remains high. During routine SBT of 3500 samples for the National Marrow Donor Program, we have identified 20 new HLA-C alleles reported in this article in 26 individuals. New variants have been characterized by direct sequencing of polymerase chain reaction product obtained by allele-specific amplification of potential new alleles. Most of the new alleles carry coding substitutions of residues located within the antigen-binding groove. The substitutions are predominantly located in the alpha2-helix which is consistent with the unique to HLA-C conservation of alpha1-helix. Seven new alleles, or 35%, have been identified in African Americans, two of them in three and four individuals each, suggesting that these alleles may not be rare. This observation reflects the fact that the minority groups, previously under-represented in the HLA research pools subjected to SBT, now begin to emerge as a main source of new HLA-C alleles. This study further confirms that HLA-C locus is at least as polymorphic as HLA-A and HLA-B.

Stress and dysmenorrhoea: a population based prospective study

BACKGROUND

Dysmenorrhoea is the most common gynaecological disorder in women of reproductive age. Despite the association between stress and pregnancy outcomes, few studies have examined the possible link between stress and dysmenorrhoea.

AIMS AND METHODS

Using a population based cohort of Chinese women, the independent effect of women's perceived stress in the preceding menstrual cycle on the incidence of dysmenorrhoea in the subsequent cycle was investigated prospectively. The analysis included 1160 prospectively observed menstrual cycles from 388 healthy, nulliparous, newly married women who intended to conceive. The perception of stress and the occurrence of dysmenorrhoea in each menstrual cycle were determined from daily diaries recorded by the women.

RESULTS

After adjustment for important covariates, the risk of dysmenorrhoea was more than twice as great among women with high stress compared to those with low stress in the preceding cycle (OR = 2.4; 95% CI 1.4 to 4.3). The risk of dysmenorrhoea was greatest among women with both high stress and a history of dysmenorrhoea compared to women with low stress and no history of dysmenorrhoea (OR = 10.4, 95% CI 4.9 to 22.3). Stress in the follicular phase of the preceding cycles had a stronger association with dysmenorrhoea than stress in the luteal phase of the preceding cycles.

CONCLUSION

This study shows a significant association between stress and the incidence of dysmenorrhoea, which is even stronger among women with a history of dysmenorrhoea.

HLA-Cw*1214 allele arisen via recombination between HLA-Cw*070201 and HLA-Cw*120201

Allelic polymorphism of the major histocompatibility complex arises mostly from gene conversion. Intralocus gene conversion usually involves limited fragments of DNA, whereas recombination involving large fragments of DNA is considered to be a rare event. During routine sequencing-based typing of donors for the National Marrow Donor Program, a new HLA-C allele was identified in a Caucasian donor. The allele, HLA-Cw*1214, proved to be the product of recombination between HLA-Cw*070201 and HLA-Cw*120201. Exons 1, 2, the 3' end of exon 3 and exon 4 (with one mismatch) belong to HLA-Cw*120201, whereas part of exon 3 belongs to HLA-Cw*070201. Sequencing with primers based in exon 2 and exon 3 showed that intron 2 of the new allele also belonged completely to HLA-Cw*1202. The recombination event apparently occurred within exon 3 with the first point of recombination somewhere between codons 92 and 134 and the second one between codons 157 and 181.

Use of whole genome amplification and comparative genomic hybridisation to detect chromosomal copy number alterations in cell line material and tumour tissue

We have established that whole genome amplification (WGA), in conjunction with genomic DNA array comparative genomic hybridisation (gaCGH) allows for the identification of genome-wide copy number abnormalities (CNAs) in DNA extracted from both cell line and patient material. To determine the fidelity and reproducibility of WGA to detect copy number imbalances using gaCGH, well characterized cell line genomic DNA was analysed. The gaCGH data obtained from non-amplified DNA and amplified DNA for the neuroblastoma cell line NUB7 and a paediatric medulloblastoma patient was almost identical. In addition, laser capture microdissection (LCM) of prostate tumour cells and subsequent WGA allowed for the detection of a number of CNAs that may not have been identified if DNA had been extracted in bulk from heterogeneous tissue. The results presented here demonstrate the use of WGA for generating sufficient DNA for gaCGH analysis without the introduction of significant sequence representation bias. The combination of amplification and gaCGH using DNA extracted from archival patient material has the potential for permitting the studying of DNA from small cancerous or pre-cancerous foci, which may help to identify potential genomic markers for early diagnosis.

Should we be worried? Investigation of signals generated by an electronic syndromic surveillance system--Westchester County, New York

INTRODUCTION

In January 2003, the Westchester County Department of Health (WCDH) began conducting electronic syndromic surveillance of hospital emergency department (ED) chief complaints. Although methods for data collection and analysis used in syndromic surveillance have been described previously, minimal information exists regarding the responses to and investigations of signals detected by such systems. This paper describes WCDH's experience in responding to syndromic surveillance signals during the first 9 months after the system was implemented.

OBJECTIVES

The objectives of this analysis were to examine WCDH's responses to signals detected by the county's syndromic surveillance system. Specific goals were to 1) review the actual complaints reported by hospital EDs to determine whether complaint data were accurately identified and classified into syndrome categories, and provide feedback from this review to data collection and analysis staff to refine text terms or filters used to identify and classify chief complaints; 2) develop procedures and response algorithms for investigating signals; 3) determine whether signals correlated with reportable communicable diseases or other incidents of public health significance requiring investigation and intervention; and 4) quantify the staffing resources and time required to investigate signals.

METHODS

During January 27-October 31, 2003, electronic files containing chief-complaint data from seven of the county's 13 EDs were collected daily. Complaints were classified into syndrome categories and analyzed for statistically significant increases. A line listing of each complaint comprising each signal detected was reviewed for exact complaint, number, location, patient demographics, and requirement for hospital admission.

RESULTS

A total of 59 signals were detected in eight syndrome categories: fever/influenza (11), respiratory (6), vomiting (11), gastrointestinal illness/diarrhea (8), sepsis (7), rash (7), hemorrhagic events (3), and neurologic (6). Line-listing review indicated that complaints routinely were incorrectly identified and included in syndrome categories and that as few as three complaints could produce a signal. On the basis of hospital, geographic, age, or sex clustering of complaints, whether the complaint indicated a reportable condition (e.g., meningitis) or potentially represented an unusual medical event, and whether rates of hospital admission were consistent with medical conditions, 34 of 59 signals were determined to require further investigation (i.e., obtaining additional information from ED staff or medical providers). Investigation did not identify any reportable communicable disease or other incidents of public health significance that would have been missed by existing traditional surveillance systems. Nine staff members spent 3 hours/week collectively investigating signals detected by syndromic surveillance.

CONCLUSIONS

Standardized sets of text terms used to identify and classify hospital ED chief complaints into syndrome categories might require modification on the basis of hospital idiosyncrasies in recording chief complaints. Signal investigations could be reasonably conducted by using local health department resources. Although no communicable disease events were identified, the system provided baseline and timely objective data for hospital visits and improved communication among county health department and hospital ED staff.